Audiobus: Use your music apps together.
What is Audiobus? — Audiobus is an award-winning music app for iPhone and iPad which lets you use your other music apps together. Chain effects on your favourite synth, run the output of apps or Audio Units into an app like GarageBand or Loopy, or select a different audio interface output for each app. Route MIDI between apps — drive a synth from a MIDI sequencer, or add an arpeggiator to your MIDI keyboard — or sync with your external MIDI gear. And control your entire setup from a MIDI controller.
Download on the App StoreAudiobus is the app that makes the rest of your setup better.
What is Audiobus 3? / audiob.us / wim
I suggest starting here: https://audiob.us, and then reporting back with specific questions if you have any after that. It would be difficult to do a better job introducing the product than its own web site does, especially without any idea how much you understand about iOS based music making, and terms like “midi”, “DAW”.
As for this forum, it has been provided by the company that makes the AudioBus program, as a place for iOS musicians to discuss the AudioBus app, other music making apps, music making in general, and even off-topic discussions (other than religion and politics). It’s an outreach of sorts, but it’s much, much more than that.